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Track Layout Diagram for Millers Dale c1900

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Re: Track Layout Diagram for Millers Dale c1900

Unread postby Mike Sheardown » Sat May 24, 2014 9:01 am

Hi Pete, thanks for your feedback.

I’ve altered the numbering of the distant signals to reflect the fact that they are not worked by the Millers Dale box (as you and Danny suggest), and the new diagram reflecting this is here:

http://i1260.photobucket.com/albums/ii565/MSheardown/LockingChartsandTables12_zpsf0d3d0dd.jpg

I’ve also read the discussion on Clare’s double slip, and applying the principles discussed there to the double slip at Millers Dale, it raises a number of questions for me, which I’ve numbered below, for ease of discussion:

1 – Firstly, I think that my lever numbering of the slip is wrong, in that I’d assumed that points 9 on my diagram set the road for either the quarry or head-shunt. However, from your reply, I assume that points 9 actually control the roads leading to points 11 or the yard, and thus the linking of points 9 and 11 as you suggest, makes absolute sense – am I right on this? (NB thus points 9 should actually be renumbered 8, and vice versa, so signal 7 is next to the point lever for which it signals the road ie 8?).

2 – Carrying on with my miss-numbering of the slip, points 8 (which you suggest should be operated by a ground lever), should now set the road for either the quarry or head-shunt?

3 – If the conclusions I’ve drawn in 1 and 2 above are correct, this then raises a question for me about the operation of signal 10, since I assume that it’s purpose is to protect the slip when points 9 are set for the up main, and thus it would be ‘on’ at these times. Further, if this is the case, it should never be passed at danger for shunting purposes as is the case for some other ground signals. However, when points 9 are in the normal position, allowing access to either the quarry road or head-shunt from the yard (as enabled by the ground lever), would signal 10 be left permanently off at these times, or would the shunter need to get the signalman to change this signal to green for each movement?

4 – Looking back at John’s diagram, I now feel that I’ve also positioned signal 7 wrongly in my diagram, and that it should actually lye between the head-shunt and quarry roads, and thus it would signal both roads when points 9 and 11 were reversed for the up main, as per the discussions on Clare. Would you agree with this also? If this is the case, unlike signal 10 above, this signal could continually be passed at danger for shunting purposes as directed by the shunter operating the ground lever at points 8.

Sorry if I’m a bit slow on all this, but I am learning, and I’m finding the help you folks are offering really useful!!

Best wishes

Mike
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Re: Track Layout Diagram for Millers Dale c1900

Unread postby John Hinson » Sat May 24, 2014 10:16 am

Mike Sheardown wrote:I’ve also read the discussion on Clare’s double slip, and applying the principles discussed there to the double slip at Millers Dale

I wouldn't focus too heavily on Clare as that particular location was not typical.

Mike Sheardown wrote:1 – Firstly, I think that my lever numbering of the slip is wrong, in that I’d assumed that points 9 on my diagram set the road for either the quarry or head-shunt. However, from your reply, I assume that points 9 actually control the roads leading to points 11 or the yard, and thus the linking of points 9 and 11 as you suggest, makes absolute sense – am I right on this? (NB thus points 9 should actually be renumbered 8, and vice versa, so signal 7 is next to the point lever for which it signals the road ie 8?).

What I would be inclined to do would be to:
  • Renumber both 9s as 8
  • Change both existing 8s to GL
  • Change 11 to 8

Mike Sheardown wrote:this then raises a question for me about the operation of signal 10, since I assume that it’s purpose is to protect the slip when points 9 are set for the up main, and thus it would be ‘on’ at these times. Further, if this is the case, it should never be passed at danger for shunting purposes as is the case for some other ground signals. However, when points 9 are in the normal position, allowing access to either the quarry road or head-shunt from the yard (as enabled by the ground lever), would signal 10 be left permanently off at these times, or would the shunter need to get the signalman to change this signal to green for each movement?

It was probably left "off" for shunting, but that might not be how it should have been done!

Mike Sheardown wrote:4 – Looking back at John’s diagram, I now feel that I’ve also positioned signal 7 wrongly in my diagram, and that it should actually lye between the head-shunt and quarry roads, and thus it would signal both roads when points 9 and 11 were reversed for the up main, as per the discussions on Clare. Would you agree with this also? If this is the case, unlike signal 10 above, this signal could continually be passed at danger for shunting purposes as directed by the shunter operating the ground lever at points 8.

Assuming my diagram is accurate, it should be positioned adjacent to the main line. It will apply to any Up departing traffic. Yes - the shunter, by arrangement with the signalman, would authorise movements for the straight route.

The history behind this is that such signals were originally "point indicators" - they simply indicated that the points had been set. They weren't originally considered as proper signals but time moved on leaving older signalling arrangements to be used for more modern functions. 10 was probably a later addition to stop shunt movements while movements took place to/from the quarry.

Mike Sheardown wrote:Sorry if I’m a bit slow on all this, but I am learning, and I’m finding the help you folks are offering really useful!!

No problem, it does us good to have to think hard about these things!

John
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Re: Track Layout Diagram for Millers Dale c1900

Unread postby Mike Sheardown » Sat May 24, 2014 11:40 am

Hi John,

Thanks very much for that, you’ve certainly answered a lot of my questions!!

I’ve altered the diagram to reflect the changes you suggest in the re-designation of points 8, 9 and 11, and I’ve added those not now in use to the spares. I’ve also re-sited signal 7 to lye adjacent to the main line, and I’ve taken the liberty of re-drawing all the points operated by the signal box, with their blades open, which I’m assuming is the correct convention?

Here’s the new diagram:

http://i1260.photobucket.com/albums/ii565/MSheardown/LockingChartsandTables14_zpsf25e51b5.jpg

A couple of other points:

With the re-positioning of signal 7, would it still signal both the head-shunt and quarry roads, or only the former?

Also, the numbering of the levers has quite a few gaps in it now, could these be better arranged for operation of the lever frame in the signal box, and if so, what would be the best configuration?

Best wishes

Mike
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Re: Track Layout Diagram for Millers Dale c1900

Unread postby John Hinson » Sat May 24, 2014 12:53 pm

Mike Sheardown wrote:I’ve taken the liberty of re-drawing all the points operated by the signal box, with their blades open, which I’m assuming is the correct convention?

Looks good for that.

Mike Sheardown wrote:With the re-positioning of signal 7, would it still signal both the head-shunt and quarry roads, or only the former?

Both.

Mike Sheardown wrote:Also, the numbering of the levers has quite a few gaps in it now, could these be better arranged for operation of the lever frame in the signal box, and if so, what would be the best configuration?

The numbering is fine, and a few spares are not unusual. The only thing I would say, on a matter of detail which may not be important to you, is that Midland Railway lever frames were manufactured in units of four levers, so a layout like this would typically be with a total of 20 or 24 levers.

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Re: Track Layout Diagram for Millers Dale c1900

Unread postby Mike Sheardown » Sat May 24, 2014 5:15 pm

Thanks again John – that’s pretty much sorted all my queries regarding Millers Dale’s track diagram.

I'm going to go for a 20 lever frame, as this will save on the expense of an additional 4 levers that aren't actually needed. I will be left with one spare however, and I will allocate this to number 11, as after shuffling everything along, this will separate off the bay and all the down main line signalling.

I’m now going to spend some time designing a locking table and locking chart for this signalling scheme, as I intend to make the mechanical interlocking myself, albeit with parts supplied by the manufacturer of the lever frame. I find all this absolutely fascinating, as too, the need to operate this station and yard in the same manner as they did back in the late 1800’s. I have a copy of the WTT for 1898 that I purchased from the Midland Railway Society, and this will form the basis of the traffic movements that take place.

One final query regarding your signalling diagram. The post with the up starter has a line at it’s base with 2 arrows on it, one pointing to the down main line and the other pointing to the up main line. I'd like to ask what these 2 arrows mean, particularly in terms of the siting of the actual signal? Previously, I'd assumed that it simply meant that it was sited on the up side, but now I'm not so sure.

Best wishes and thanks again

Mike
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Re: Track Layout Diagram for Millers Dale c1900

Unread postby John Hinson » Sat May 24, 2014 5:42 pm

Mike Sheardown wrote:One final query regarding your signalling diagram. The post with the up starter has a line at it’s base with 2 arrows on it, one pointing to the down main line and the other pointing to the up main line. I'd like to ask what these 2 arrows mean, particularly in terms of the siting of the actual signal? Previously, I'd assumed that it simply meant that it was sited on the up side, but now I'm not so sure.

The arrows show which line(s) the signal(s) applies to - in this case both as the post carries the home for one direction and the starter for the other. The physical position of the signal differs between my plan and yours - it may be that you have physical evidence in photographs that proves mine to be incorrect but if not I suspect it was on the outside of the curve (as I show it) for best sighting from the footplate.

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Re: Track Layout Diagram for Millers Dale c1900

Unread postby Mike Sheardown » Sat May 24, 2014 7:21 pm

Well, I've learnt something new again here!! I always thought that the arrows pointed to the actual site of the signal, when there wasn't room to draw it in it's correct position. I think that I'll need to revisit my diagram, and reposition a number of my signals!!

Your position of this particular signal is right, as evidenced by one of the very few photos I've seen of this station at this period.

Thanks

Mike
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Re: Track Layout Diagram for Millers Dale c1900

Unread postby Danny252 » Sat May 24, 2014 7:37 pm

Mike Sheardown wrote:Well, I've learnt something new again here!! I always thought that the arrows pointed to the actual site of the signal, when there wasn't room to draw it in it's correct position. I think that I'll need to revisit my diagram, and reposition a number of my signals!!


In the case where a signal doesn't fit, I've usually seen them indicated with letters (at least for John's drawings), e.g. a signal marked "X" would be found at the corresponding location denoted by an "X". The normal case is that the base of the signal post (or bracket/bridge) indicates the position of the signal.
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Re: Track Layout Diagram for Millers Dale c1900

Unread postby Mike Sheardown » Sat May 24, 2014 8:05 pm

Thanks for the extra explanation Danny

Cheers

Mike
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Re: Track Layout Diagram for Millers Dale c1900

Unread postby Mike Sheardown » Sun May 25, 2014 1:45 pm

I’ve now redrawn the signalling diagram to reflect the renumbering of points and signals for a 20 lever frame, and I’ve also re-positioned some of the signals that I had originally sited wrongly. This final version is now shown here:

http://i1260.photobucket.com/albums/ii565/MSheardown/TrackDiagramMD1_zps3834f53b.jpg

I have then gone on to use this diagram as the basis for designing a Locking Table, and this is shown here:

http://i1260.photobucket.com/albums/ii565/MSheardown/LockingTableMD2_zps03e611de.jpg

I’d be very grateful for any advice regarding the following:

1 – Have I named the various levers appropriately?

2 – Is the interlocking correct for the protection of traffic?

Many thanks for your ongoing help with this project, it's very much appreciated!!!

Mike
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Re: Track Layout Diagram for Millers Dale c1900

Unread postby Pete2320 » Mon May 26, 2014 1:37 pm

Regarding the interlocking, 19 would usually lock 4, 10 and 12 (and vv) Also, at least on a purely mechanical layout such as this, the starters would usually lock trailing points in rear "either way". However I wonder if the MR would have done this at this time as it is quite complicated to do with Tumbler locking. Otherwise the locking looks OK but I'm not really in a good circumstance at the moment to thoroughly check it.

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Re: Track Layout Diagram for Millers Dale c1900

Unread postby John Hinson » Mon May 26, 2014 2:29 pm

Pete2320 wrote:However I wonder if the MR would have done this at this time as it is quite complicated to do with Tumbler locking.

They would. It was a BoT requirement and whilst exemptions might be granted in special circumstances "it's too difficult" wouldn't be one of them.

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Re: Track Layout Diagram for Millers Dale c1900

Unread postby Mike Sheardown » Mon May 26, 2014 4:14 pm

Thanks Pete and John,

Pete, I'll add the changes you suggest to the locking table, but can I ask why 19 would also need to lock 4, 10 and 12, when 18 is already doing this? Is it because the clearing point for 19 would be fouled if 4, 10 or 12 were being worked with 19 off, and thus an approaching down train would really need to be brought to a stand at 18, and 19 returned to on, prior to 4, 10 or 12 being reversed for the movement of traffic?

Mike
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Re: Track Layout Diagram for Millers Dale c1900

Unread postby Pete2320 » Mon May 26, 2014 8:02 pm

Mike Sheardown wrote:Thanks Pete and John,
Is it because the clearing point for 19 would be fouled if 4, 10 or 12 were being worked with 19 off, and thus an approaching down train would really need to be brought to a stand at 18, and 19 returned to on, prior to 4, 10 or 12 being reversed for the movement of traffic?
Mike

Yes that's what would be done, or the train just held at 19. The overlap for the block would be 440 yds in advance of 19 which I think would include all the pointwork. As such it would not be permittted to accept a train from the box in rear if 4, 10 or 12 were reversed. I have already mentioned that 19 was provided largely to comply with an obsolete (since block working was introduced) requirement to have a stop signal protecting a train stood at a platform so as such I can see why you might think it need not be interlocked with the points ahead of 18. However, I'm certain it would have been and was probably a BoT requirement. I'm conscious that this answer is simply saying "thats how it was done" without really explaining why. Hopefully somebody will give a more concise reason.

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Re: Track Layout Diagram for Millers Dale c1900

Unread postby Mike Sheardown » Mon May 26, 2014 9:05 pm

No, I found your explanation really helpful, and I understand the need for the 1/4 mile clearing point, but had failed to take it into account with regard to 19. Now that I think about the implications of this more fully, am I right in saying that where any use was being made of the down main line, down trains could only be accepted under the warning arrangement? Further, under these circumstances, irrespective of the section of line between 18 and 19 being unoccupied, 19 would need to remain on until the approaching train was brought to a stand at 19, and then if desired, 19 could be pulled off, and the train allowed to move up to 18.

This is all good learning for me, and I appreciate both yours and everyone elses help, in answering my many queries.

Cheers

Mike
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